Spine surgery showdown: which Tiny-Incision procedure wins for seniors?

Copied word for word from the study's registry entry, so the wording is the study team's rather than ours.

Inclusion Criteria: 1. Aged between 50 and 75 years, regardless of gender. 2. A definitive diagnosis of lumbar spinal stenosis, presenting with typical clinical symptoms (e.g., lower extremity radiating pain, neurogenic claudication) and signs, confirmed by imaging (MRI or CT). 3. The lesion involves only a single spinal segment (L2-S1). 4. Failed to respond to at least three months of systematic conservative treatment, with a significant impact on quality of life, and the patient has a clear willingness to undergo surgery. 5. (Clinical equipoise) After evaluation by at least two senior spine surgeons, both agree that the patient's condition meets the surgical indications for both full-endoscopic decompression and endoscopic lumbar interbody fusion. 6. The patient fully understands the randomized nature of this study (including random assignment and the relinquishment of choice by both the physician and the patient) and voluntarily signs the Informed Consent Form. Exclusion Criteria: 1. Clear indications for fusion: Degenerative spondylolisthesis greater than Meyerding Grade I, presence of lumbar spondylolysis, or evidence of definite lumbar instability on flexion-extension radiographs (e.g., segmental translation \> 3 mm or angular change \> 10°). 2. Clear indications for decompression alone: Stenosis caused solely by soft disc herniation, without concomitant bony spinal canal or lateral recess stenosis. 3. Spinal stenosis due to non-degenerative causes: Presence of spinal stenosis caused by fracture, spinal tumor, active infection, or inflammatory disease (e.g., ankylosing spondylitis, rheumatoid arthritis). 4. Severe spinal structural abnormalities: Presence of severe spinal deformity (e.g., degenerative scoliosis with a Cobb angle \> 20°). 5. History of relevant prior surgery: Previous lumbar surgery at the same or an adjacent segment. 6. Systemic diseases precluding tolerance to surgery: Presence of severe dysfunction of major organs (e.g., heart, lung, liver, kidney) or an American Society of Anesthesiologists (ASA) classification \> III, indicating an inability to tolerate anesthesia or surgery upon evaluation. 7. Comorbidities that may confound outcome assessment: Presence of other conditions that could cause lower extremity claudication or dysfunction, such as severe hip or knee osteoarthritis (including a history of total hip or knee arthroplasty), peripheral vascular claudication, or polyneuropathy. Presence of other neurological or muscular system disorders that could seriously affect treatment evaluation (e.g., Parkinson's disease, amyotrophic lateral sclerosis). 8. Participation in other studies: Currently participating in other clinical trials that could potentially influence the results of this study.